On Mon, 2019-06-10 at 11:54 +0200, Luigi Toscano wrote:
- the email's subject helps a lot (it's even too chatty)
In this case perhaps, but very often that simply isn't true. You need
the actual context.
- your email client should be able to properly use threading.
It does. That does not relieve the poster from quoting the actual part
of the message he's responding to. To argue otherwise is like saying
no-one should quote anything in replies.
To be clear, the habit of some posters who just dump the entire (often
long) message into their reply is almost as bad.